1. Field of the Invention
The present invention relates to emergency alarm systems for buildings. More particularly, the present invention relates to a directional fire alarm system for indicating the exit and the path towards the exit for evacuees throughout a given building, relative to the detected fire location(s).
2. Description of the Related Art
It is known in fire fighting circles that when a fire breaks out, time is of the essence, and that building occupants must proceed to the nearest exit in an orderly, yet timely fashion. Typical fire alarm systems in buildings, such as those described in U.S. Pat. Nos. 4,556,873, 5,627,515, 4,697,172, and 6,281,791, all of which are hereby incorporated by reference, generally detail fire alarm systems with threat sensors that detect the presence of a fire and perhaps its general location according to a zone, the data of which are relayed to a central box, typically situated in a lobby for reading by authorized personnel. However, these systems are generally “dumb” systems that do nothing more than sound a siren or alarm to alert building occupants of a fire, (who must follow unmarked paths to an illuminated “EXIT” sign posted above an exit) and do not provide occupants and/or rescuers with useful escape information based on the relative spatial threat of a fire.
As such, many deaths and injuries occur because of poorly marked exit paths, or because the locally mandated exit signs are obscured by smoke and/or darkness that typically occur during an emergency such as a fire, earthquake, explosion, gas release, black-out, and the like. Moreover, the presently known alarm systems are both expensive and difficult to produce, install and maintain, and often do not address a variety of emergency situations other than fires. Additionally, prior art systems merely provide an audible alarm sound, or in more “advanced” systems, fixed strobe lights or stationary “exit” lamps fixed at exit. Furthermore, exit lamps that are used in conjunction with conventional fire alarm systems consume excessive power from battery operated emergency power supply systems and therefore fail to effectively produce sufficient light after an initial period of operation. In addition, conventional exit lamps are unreliable because they can unpredictably burn out at the time of emergency use. In addition, the indication lamps and arrangements in conventional systems are difficult to see and understand during emergency situations. Conventional systems also fail to provide information about alternative routes of egress.
Nevertheless, there have been attempts in the prior art to overcome some of these problems in directing evacuees to exits, but none provide a means to direct evacuees from all areas and floors of a building away from the direction of a fire reported by a fire alarm system. For example, U.S. Pat. No. 5,140,301 by Watanabe, and U.S. Pat. No. 6,181,251, by Kelly, disclose various laser directional means for pointing down the length of a hall way or room, towards a an exit. These types of systems, however, do not offer panicked evacuees a clear sense of direction, given that a laser may point from say, point A to Point B, but cannot show whether one should proceed towards point A, rather than point B, or vice-versa. Even where such systems attempt to point to a direction by decreasing the slope from say, high to low along the length of a space, for long lengths of corridors, this method does not work as well as in smaller confines. In any case, however, this approach is fraught with shortcomings in that it is not an immediately obvious, fool-proof means of directing evacuees toward an exit, especially if such evacuees have not been already instructed in the interpretation of such laser points.
In addition, U.S. Pat. No. 5,572,183, Sweeney, discloses a laser light evacuation system that directs multiple vertical columns of lights from the ceiling to the floor of a corridor, in which the lights are sequenced from left-to-right and right-to-left during a fire to direct people to the nearest safe exit. However, this approach too, is not immediately intuitive to panicked evacuees who may not understand the meaning of sequenced columns of vertical lights throughout corridors.
Finally, U.S. Pat. No. 4,801,928, by Minter, hereby incorporated by reference, discloses an egress direction indication system having at least three electroluminescent lamps in a linear arrangement and circuitry for sequentially illuminating the lamps on a repeated basis from one end of the arrangement to the other so as to provide a direction for evacuees in response to a relative danger,such as a fire. However, Minter, does not provide a solution for such notification on a wholesale, building-level approach that can be used to reflect the danger to occupants on other floors/areas from a fire on a different floor/area. Moreover, Minter does not allow for a system that can provide real-time, large-scale intelligence to firemen and other responders to the scene of an alarm. As seen in many recent fires, the fact that fires and/or explosions may have destroyed entire sectors in a building, imparting that particularized geographical knowledge and associated condition data to both evacuees and firemen is vital for maximizing the effectiveness of individual escape efforts, as well as for immediate, intelligent planning of fire fighting and/or rescue operations.
Accordingly, none of the other systems in the prior art provide a solution to indicate the safest exit in a universally understandable, intuitive manner such that all evacuees, anywhere in a building, can immediately grasp the correct direction towards an exit relative to a fire (or fires), wherever it (and they) may be located. In addition, none of the prior art offers intelligent output from such a system, so that firemen and responders can accurately understand the scope of the emergency at hand.